public override void Bind( RenderTarget target )
{
/// Check if the render target is in the rendertarget->FBO map
GLFrameBufferObject fbo = (GLFrameBufferObject)target[ "FBO" ];
if ( fbo != null )
fbo.Bind();
else
// Old style context (window/pbuffer) or copying render texture
Gl.glBindFramebufferEXT( Gl.GL_FRAMEBUFFER_EXT, 0 );
}